Alpha melanocyte stimulating hormone (alpha-MSH) is released from UVR exposed keratinocytes in human skin following exposure to ultraviolet radiation. It is understood to act on the melanocortin-1-receptors (MC1R) to, exclusively in melanocytes, induce synthesis of the brownish-black melanin pigment. MC1R are expressed on keratinocytes as well as number of other cells including, but not exclusively, immunological cells such as dendritic/Langerhans cells, neutrophils, microglia and monocytes as well as astrocytes, and endothelial cells.
It has previously been disclosed that a super-potent derivative of alpha-MSH, Nle4-D-Phe7-α-MSH, can induce melanin synthesis in human volunteers. Nle4-D-Phe7-α-MSH contains two amino acid substitutions and is approximately 10 to 1,000-fold more potent than the native hormone at inducing pigmentation in experimental systems such as the frog skin bioassay or in cultured human keratinocytes.
There is a need for methods for treatment or prevention of photodermatoses which include skin reactions to UVR, including by way of example, phototoxicity, photoallergy including actinic dermatitis and solar urticaria, idiopathic reactions including actinic prurigo and polymorphous light eruption, metabolic and nutritional reactions including erythropoietic protoporphyria, DNA-deficient photodermatoses including xeroderma pigmentosum, epidermalysis bullosa, photoexacerbated dermatoses and chronic photodamage.
The present invention provides a method for prophylactically or therapeutically treating photodermatoses by administration of an alpha-MSH analogue.
Bibliographic details of the publications referred to in this specification by reference number are collected at the end of the specification.
The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.
Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications, the invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations or any two or more of said steps or features.